It really takes a lot for me to remove the helmet. I've had issues where I really wanted to remove it and did not. However, if I am terrifying a child, I will show them I am a person under that helmet. Only as a last resort. At the last con I went to, a service dog was very upset by me. The owner asked me to let the animal see me and I complied. The dog realized I was not a threat and was not intimidated by the rest of the troops.
I don't remove my helmet easily, but sometimes it is necessary. Real life sometimes calls for it.